We were a-head of our time.
A reconstruction of a one-million-year-old skull suggested that our species started to emerge hundreds of thousands of years earlier than previously believed, according to a brainy new study published in the journal Science.
“From the very beginning, when we got the result, we thought it was unbelievable. How could that be so deep into the past?” said Prof Xijun Ni of Fudan University, who co-led the analysis, the BBC reported.
Dubbed Yunxian 2 skull, the ancient cranium was reportedly exhumed in 1990 from an archaeological repository in Hubei province in central China, Livescience reported.
For decades, researchers thought that the primeval noggin belonged to Homo Erectus, the first large-brained humans, because it dated back a million years — long before the first advanced humans were believed to have emerged.
This early hominid eventually evolved until 600,000 years ago, when it split into Neanderthals and our line, Homo sapiens, the BBC reported.
However, after using CT scans to create digital restorations of the face, which was crushed and distorted when it was discovered, a team of researchers from China and the UK revealed that it actually belonged to an early Asian hominid line called the Denisovans.
Despite going extinct nearly 30,000 years ago, their existence was only just revealed in 2010 through DNA evidence.
The traits — including a large cranial capacity, a long and low frontal skull bone, and a narrow space between the eye sockets — were specifically consistent with the Homo longi clade, a species that was as advanced as Neanderthals and Homo Sapiens.
“The Homo longi clade, containing the Denisovans, lasted for over a million years,” study co-author Chris Stringer, a paleoanthropologist at the Natural History Museum in London, told Live Science. “But so did the Neanderthal and sapiens lineages.”
In fact, evidence suggests that Yunxian 2 lived alongside them, meaning that all three species likely cohabitated the planet a million years ago.
If this striking analysis is correct, it would mean that large-brained humans came on the scene a half a million years earlier than previously thought.
“We tested it again and again to test all the models, use all the methods, and we are now confident about the result, and we’re actually very excited,” exclaimed Professor Ni.
In fact, Stringer believed that there are probably one-million-year-old fossils of Homo Sapiens that have yet to be discovered.
The evidence also suggests that the three species diversified rapidly, although the cause of their accelerated divergence remains unclear. However, as the time frame got pushed so far back for the emergence of this evolutionary trio — which each lived in small isolated environments — Stringer believes that we can look back earlier in time to pinpoint the catalyst for this rapid evolution.
“For example, there were two severe cold events at about 1.1 million and 900,000 years ago, and that may have catalyzed evolutionary and behavioral changes,” he said.
Of course, there are some caveats to the research. Experts were concerned over the accuracy of the methods that the team used to determine the species and when they walked the Earth, which entailed analyzing the shape of the skull and its genetic data.
“One has to be particularly tentative about the timing estimates, because those are very difficult to do, regardless of what evidence you’re looking at, be that genetic or fossil evidence,” said Dr. Aylwyn Scally, an evolutionary geneticist at Cambridge University in the UK. “Even with the largest amount of genetic data, it is very difficult to place a time when these populations may have co-existed to within 100,000 years, or even more.”
So while it is tempting to conclude that our species might have originated in Asia — especially as the earliest known evidence of Homo sapiens in Africa is just 300,000 years ago — there is not enough evidence to confirm this is the case right now, per Stringer.